The distribution and daily movement of stone crabs (menippe mercenaria) in an intertidal oyster habitat on the northwest coast of Florida

The distribution and daily movement of stone crabs inhabiting a semi‐artificial, intertidal, oyster habitat was monitored from May to December, 1983, on the northwest coast of Florida. The population structure was characterized by an abundance of adult males and juveniles of both sexes in the summer followed by an influx of adult females during the early fall mating season. Adult heterosexual pairs were sighted exclusively in September and October. Adult males in heterosexual pairs were significantly larger than unpaired adult males. Paired and unpaired females did not differ in size nor were the sizes of paired individuals correlated. Nearest neighbor analyses indicated adult males were distributed randomly during the pre‐mating, mating and post‐mating seasons. Tag‐recapture data indicated there were no differences in frequency or distance of movement between the sexes or size classes. The higher frequency of pairing for large males suggests non‐random mating occurred; however, a behavioral mechanism explaining this pattern (e.g. either extended resource defense or high movement frequencies) was not evident.